“Popular Science,” Nov 2012: “To measure the water resistance of Down Décor’s insulation, we set up a side-by-side test against untreated down. We poured a half cup of water into jars with a quarter cup of fill and left both samples to sit for five minutes. We then removed the fill and timed how long it took each sample to dry naturally. When removed, the Down Décor fill retained only a couple drops of water; the untreated down held on to about 5 milliliters. The Down Décor fill dried within an hour and lost none of its loft, while the sticky, wet blob of untreated down took a full weekend to dry completely.” "This year, 3 companies developed methods of water-proofing the feathers without losing loft... Down Decor mists the down with a layer of per-flouro-alkyl acrylate..." Page 22

That's a fine test, but how does that relate to what would happen in reality.

You should take two down garments - one regular and one water-roof down. Put them out in the rain during a storm that rained 0.1 inch (or whatever). It would be interesting to weigh each sample to see how much water it absorbed. And then put it on a human body and measure it's warmth.

My question is how waterproof will that down be after repeated cycles of being stuffed and unstuffed? Down that is partly waterproofed and partly not might just get wet in the end and take even longer to dry.

I don't think a rain test is very useful either. Now if the down garment were in a chilled environment and steamed were passed through it, it'd simulate sweat vapor passing through and condensating in the insulation. Or better yet, do the same thing in a high humidity environment with the temperature a little above freezing. Nightmare conditions for down.

Water repellent coatings typically reduce the material's surface energy; this is relevant to preventing water in a liquid state from being absorbed.

Water repellent coatings do not typically change the material's moisture regain value; this is relevant to preventing water in the gaseous state (high humidity from the external environment or evaporated sweat) from being absorbed.

There are at least three competitive down water repellent coating products being promoted. Liquid state protection looks adequate for all three based on just putting the coated down in a container with water and shaking. This is the half of the story that I am least interested in since I have always been able to use a dry bag, shelter, or shell, to keep liquid water out of my down for my typical outings. Moisture regain is an industry standard test that would clearly show how the products compare to the same down without the water repellent coating.

I won’t be buying any of these products until I see the water gaseous state test results.

Looks like there is more than one way (treatment chemical) to "waterproof" down. Let's sit back and see what happens in the real world as others put it to the test.

OR... our intrepid garment tester Will Reitveld could gather the various down waterproof brands, say down jackets, and test them himself. That's a test I would trust.

BTW, one of the real tests of any WPD (waterproof down) chemical is how much, if any, does it reduce teh roiginal loft. Tough to pay for natural down of 800 fill when the WPD treatment makes it 700 fill.

"BTW, one of the real tests of any WPD (waterproof down) chemical is how much, if any, does it reduce teh roiginal loft. Tough to pay for natural down of 800 fill when the WPD treatment makes it 700 fill."I do not think it effects loft. From DriDown's web site:"...While down of a specific fill power is the same across the board,..."

This and other questions need to be answered. Unfortunatly, it is only being offered on low fill downs, ie 550/600. The best I have seen *is* 800(EN or American?)in some jackets, but there is no spec on the actual starting fill, before treatment, that I have been able to find... Nothing that says it reduces loft. Nothing that says it increases loft. I think this would change slightly if it disrupts or enhances the static electricity repulsion, but not by a measurable amount...especially given the variability of down plumes.

Richard, from DriDowns web site I get this:"...Apparel and sleeping bags insulated with DriDown™ will perform better right away. Even small amounts of sweat or humidity will begin to diminish the performance of untreated down. DriDown™ will keep even the smallest amount of moisture from negatively impacting down performance."*and*"Untreated down plumes collapse when wet, reducing loft and insulating efficiency. DriDown’s™ water resistance far exceeds that of untreated down, staying dry 10-times longer in the presence of natural body moisture, humidity, rain, and snow to offer superior loft and thermal efficiency in any environmental situation."

I am not sure they even understand the difference between water vapour (gas) and water (liquid) and ice (solid.) As with many people, they could well be confusing water (liquid) with water vapour(gas.) Nor, do they understand how water vapour changes phase to a liquid. Example: Glass is a pretty good water proof material. Yet condensation on windshields still happens.Example: Silnylon is quite hydrophobic, but, we get condensation on it. (Worse, the droplets are quicker to come off.)

I strongly suspect it could reduce the actual formation time slightly by reducing the number of "seed" sites available. But,it doesn't really matter. Dridown does not protect the down from water in a long term wet-out, anyway. It is NOT a total water proofer for down. More like a DWR coating on the plumes. I would expect some sites to be closed, but, there are literally millions of seed sites within down, treated or untreated. Water molecules have an afinity for other water molecules, indeed this causes condensation, soo, I expect condensation to occur in dridown about the same as normal down. Only the adhesion or "stickiness" of water is *clearly* different. The condensation droplet will be rounder, since, it will not wet out the plume, allowing it to stick. (Other ramifications...)Example: Condensation on glass. If treated with RainX, it will bead. If untreated the bead shape is different. But, it still happens.

Only the rate of formation will be slightly different. Likely, a reduced amount of vapour will condense, but the difference is surely minimal. Condensation will occur in the down. But, since it does not wet it out as fast, there will be some noticable benefit from reduced drying time. And, since the plumes are hydrophobic, it will not wet them, saturating the plume's molecular structure. Again, reducing drying time for this aspect.

Local supersaturation is likely to foster movement to outer layers, per normal for all down. It will migrate to the colder layers nearer the outside of the bag due to vapour<->water equilibrum from the surface area of the droplets. I suspect that the more spherical shape will slow this migration.

Other statements about DriDown can be seen here: http://www.dridown.com/faq/

On another thread the poster measured the loft of his Brooks Range Mojave hoody with 9oz of 800fp down using box wall construction, I do not remember the exact results but my Gooses feet Parka with the same amount of down (900 fp) was twice as lofty.

Backpacker mag had the LL Bean jacket (850fp downtek) in it's winter test and it received high marks:

"Wore it 3 days or rain fog and drizzle, shell-less in northern Scotland. My partners regular down jacket collapsed into a sodden mess within hours but the LLBean stayed fluffy and warm and dried fast in my bag each night."

Hardly a scientific, controlled test, but when the results are this different, I'd say it works!

Yeah, if this stuff works, this is what I am going to. Can't wait for the review on Backpacker.

The LL Bean jacket comes in a very good tall. They say the average weight of it is 14 oz using 20 denier 1.1 oz shell material. I don't know what the fill oz. are as they did not know but I would guess from the pic to be about 3oz or a smidge more. Might be this year's Christmas present. I really don't mind it not having a hood as I don't use them anyways. Now I just might have to wait for the cottage manufacturer's like Enlightened Equipment to make a quilt using this stuff.

One of GearJunkie's guys tested Sierra Design's Cloud Puffy in his shower and said it performed excellently. I actually picked up one of the Sierra Designs Zissou bags with DriDown at an REI garage sale, and while it's been a great bag so far I haven't had it in any conditions that would test the DriDown. Either way I'm still happy with it and it'll be my bag for Rainier next year.

I don't know how many of you guys have heard of KUIU before, they make mountain hunting clothing, they are coming out with some products using Toray Quix down, according to thier blog it will be made with 850 fill with polish down. Here is the website http://blog.kuiu.com/ i have had good luck with all thier products that they make, pretty excited about thier version of water proof down

Yeah, mostly bags, I guess....Here is the artical I was thinking of...http://sectionhiker.com/hydrophobic-down-sleeping-bags-and-jackets/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+Sectionhikercom+%28sectionhiker.com%29